WordPress makes installing a free theme on your blog quick and simple.
Login to your wordpress admin panel.
Choose the Appearance menu option and click Themes.
Click on the Add New Theme button.
Type a keyword or the name of a template in the search box.
When you find a theme you like the look of hover over it and click the Preview button to preview it or the Install button to install it.
Once the template is installed you’ll need to set it as the active template by clicking Activate.
If you head back to the themes page you’ll see your new theme as the active theme.
There are loads of amazing free blog designs out there and it’s a nice way to personalise your blog if you don’t know how to code or don’t want to shell out for a premium theme just yet.